Slide-based presentation applications mix time-based concepts (such as animations and transitions) with slide-based concepts (such as objects on slides). This often leads to unnatural product limitations. For example, it is sometimes desirable to transition from one slide to a next slide while keeping an object from the first slide in the exact same place in the next slide. In slide-based presentation applications, this is done by including a copy of the object in both slides. In another example, a user may wish to include an animation in a slide. The animation may include replacing one shape with another shape in the same location. In slide-based presentation applications, this requires positioning one shape directly on top of another, making it cumbersome to select the bottom shape. Slide-based presentation applications also make it difficult to see what the presentation view looks like at a particular time midway through the slide.